miR-125a-3p targetedly regulates GIT1 expression to inhibit osteoblastic proliferation and differentiation.

Osteoblasts are a prerequisite for osteogenesis and bone formation, and play a key role in metabolic balance, growth, development and wound repair. G protein-coupled receptor kinase interacting protein 1 (GIT1) and a series of miRNAs are known to have important effects in the growth and migration of osteoblasts, but little is known about micro RNAs (miRNAs) targeting GIT1. The present study found that miR-125a-3p has matching sites on GIT1. In the osteoblastic differentiation process of human bone marrow-derived mesenchymal stem cells (HMSCs), the expression of miR-125a-3p was suppressed compared with that in non-differentiating (HMSCs) while the expression of GIT1 showed a gradual and significant increase. Thus, miR-125a-3p expression was negatively correlated with the expression of GIT1. Following the transfection of human osteoblasts with miR-125a-3p mimics and inhibitors, respectively, the effect on GIT1 expression was opposite to the change of miR-125a-3p expression. In addition, the impact of miR-125a-3p and GIT1 on osteoblastic proliferation and differentiation was detected, and the results indicated that miR-125a-3p targetedly regulated GIT1 expression to inhibit osteoblastic proliferation and differentiation. These findings may provide a theoretical basis for clarifying the physiological and pathological role of miRNAs in osteoblast differentiation and maturation processes, and for the physiological and pathological investigation of bone.